Crashed Futura V3

[davidk]

Last week I was flying the FMS Futura V3 and on my 1st flight, 2nd circuit it felt odd.  I realized I didn't have full aileron control... or at least as much as should have had.
I was able to slow down, control it, and land.
I found that my right aileron servo was not responding... and then it did... but intermittently.
When I got home I powered on the Futura and hammered at that servo, banging it, deflecting it... over and over and over for 10-15 minutes.  I could not get it to fail.
I checked all the connections... all good.
I flew it today... and it failed again... very badly this time.  I could not get it back.
It went down hard in the lumberyard.  Mark was kind enough to trek through the brush with me and we found a 30 yard debris field on both sides of the river.
We collected all major parts, the battery was crushed (brand new Spektrum 4000), and made it out with only a few scrapes.
Thank goodness the gear was up.
I really do wonder if the Aileron servo went bad... because I could not get it to fail when it wasn't flying.
I wonder if it was the control board.  We'll never know.

Below is a list of parts I was able to salvage and their retail prices.  I priced my collection only for interest sake.  The parts will come in handy for other projects and/or as backups for the next Futura.

Motor (no fan) : $75
Main Gear : $120
Front Gear : $64
Reflex V2 : $29
Blue Predator 100A ESC : $107
A few servos 13g Digital Metal (not from the Ailerons)

Total $395 Retail worth of parts.  Full plane : $525

[davidk]

Update on the Aileron issue.  I don't think it was the Aileron servo that went bad.

Last night I was assembling a new Futura V3.  Everything went together fine... the rear HS screw was, again, almost impossible to install, but it got there.

The wing electrical connection is an 8-pin quick connect... very robust.

I fired up the jet and the right main landing gear would not activate.  I checked all the connections at the Reflex V2 and the Rx and all good.

I removed the right landing gear and carefully peeled back the tape covering some wires.

The aileron, flap, light, and gear wires all funnel through a pocket and attach to the quick connect.

I very carefully extracted each wire, not tugging or forcing anything.  While I did this the left main and front landing gear activated.  As I moved the wires again, the gear activated again.

And, the aileron servo would shudder.

I managed to get all the wires out of the pocket and disconnected the right gear.  I tested it separately and it worked.

I plugged the gear back in and it works.  Then I started moving the wires around and nothing happened... no gear activation and no aileron servo movement.

I gently put everything back into the pocket making sure not to crimp anything.

Then I unscrewed the quick connects on both sides and made sure nothing was loose there.

I now feel there was a wiring issue at the quick connect which caused the right aileron servo to stop responding.

I remember Michael had a similar problem with his red Futura where a main landing gear would not activate.  He gave the wing a couple of light whacks and it would work.  This was fairly consistent until the problem went away.  I remember once he was putting the Futura on the ground and one of the main gear would activate and close.

This was probably the same quick connect wiring issue... and the take-offs and landings and wing whacks loosened up the wires enough to stop the problem.

[Gregor77]

I am going to have to agree with you, David. I've had the same issue with other airplanes at the quick connect points. It's wise during maintenance to check and do a quick wiggle if you suspect there is an issue. Sorry about the loss of the airplane, but great explanation and research.